The present invention relates to an access member and a system for catheterization of the urinary bladder through an artificial or a natural canal in a user. The invention furthermore relates to a method of replacing such an access member
Catheterization may typically be necessary in the case of postoperative urine retention of newly operated patients in a hospital. Another typical use is with patients suffering from severe cases of urinary incontinence as for disabled individuals like para- or tetraplegics who frequently have no control permitting voluntary urination.
Traditionally, such catheterization is carried out by inserting a catheter through the urethra of the patient. The catheter may be left in place for permanent catheterization during several hours or days, which is typically the case in elderly and infirm patients, or be retracted after emptying of the bladder, ie. so-called intermittent catheterization (IC).
Access to the urinary bladder may likewise be desirable in order to introduce eg. pharmaceuticals into the bladder or in order to wash or rinse the bladder.
Intermittent urethral catheterization performed with intervals of eg. 3 to 6 hours reduces the risk of infection of urethra and the bladder significantly as compared to permanent catheterization and has for many users become increasingly common also in daily life situations outside the clinical environment of a hospital, whereby a significantly improved quality of life has been obtained for this group of patients.
However, intermittent catheterization requires a certain degree of dexterity and mobility which implies that self-catheterization is not always possible, especially in women where the urethral orifice may be difficult to locate.
During recent years, suprapubic catheterization (SPC) has been introduced as an alternative to urethral catheterization. In suprapubic catheterization, a canal is made from the surface skin of the abdominal wall of a user into the bladder under local or general anaesthetia and by means of a pointed hollow introducer or trocar. After penetration of the trocar into the bladder, a catheter is inserted through the canal thus provided, the inner end of said catheter being retained in the bladder by means of eg. an inflatable balloon abutting the inner wall of the bladder after retraction of the trocar. Although many of the disadvantages connected with urethral catheterization, such as eg. urethral cleavage and urethritis, may be overcome by this technique, infection risk is still high as suprapubic catheterization is typically performed as permanent catheterization due to the fact that the canal may close during replacement of the catheter. Furthermore, the fact that the end of the catheter protrudes well into the bladder when using a balloon, which is necessarily placed at a distance from the end in order to allow in-flow of urine, means that the bladder wall may be injured, the more so as the bladder wall often assumes an at least partially collapsed position in which it rests on the end of the catheter.
GB patent No. 2 275 420 discloses a system for suprapubic catheterization of the bladder permitting intermittent catheterization by means of an accessor or sealing member permanently lodged in the artificial canal. The accessor comprises an outer shell formed by two elongate leaves of a bendable plastics material which are hinged together along one edge and having flanges at one end for securing the accessor to the skin surface. A sealing means in the form of a balloon assembly keeps the canal formed in the accessor closed between emptyings but allows insertion of the catheter. Due to the size and material of the accessor, this system may cause discomfort to the user.
Another alternative is provided by the so-called Mitrofanoff principle, by which a suprapubic canal is surgically made by removing parts of a body section, such as the appendix, another part of the intestinal system, eg. a section of the ileum, or any other suitable tubular body tissue, and subsequently attaching one end of the section to the abdominal skin surface whereas the other end penetrates the bladder wall and possibly protrudes into the bladder, the part being attached to the bladder wall at the point of penetration. Obviously, this technique requires surgery under general anaesthetia and implies a loss of bowel or other tissue as well as stitches in the bladder wall.
U.S. Pat. No. 5,704,353 discloses a catheter for temporary placement in the female urethra. The catheter comprises a shaft which in one end has a sealing portion and in the other end a cap. In the lumen of the shaft a one-way valve is enclosed, urine being drained upon activation of the valve by means of a spike. As the length of the shaft has to be adapted to the individual length of the user's urethra and due to the rather elaborate design, this device is expensive and complicated in manufacture. Furthermore, the presence of the sealing portion, which is designed as a mushroom-shaped crown and which in the position of use rests against the inner surface of the bladder, may cause discomfort to the user.